mikemarotta wrote: ↑Sun Jan 05, 2020 4:52 pm
Hankmeister3 wrote: ↑Sun Jan 05, 2020 3:20 pm SW Quattro 8 f/4 ... Single-frame, no filters ...
Thanks! I appreciate this "natural" production, d.h., what the camera and telescope delivered without post-processing.
Nice work.
And congratulations on the patience to do it.
Thanks Mike. Technically the image isn't completely
au natural. Though a single-frame, I do run all my astro-images through my ArcSoft PhotoStudio 6.0 suite at my meager attempts at "post-production" to separate
DSOs from the background fog/skyglow/noise. However, of late, I've totally revamped my simple-Simon post-production tweaks by mostly limiting them to multiple tone adjustments during my single-frame layering processing, despeckling where needed to mitigate noise and ISO "grain", minimal color balancing, white balance and oftentimes add a bit of "gaussian blur" to help smooth the (nebular) images a bit. I now only make minimal contrast and luminance tweaks since separately adjusting for highlight, midtones, and shadow (lowlights) seem to work better.
Unfortunately I can't add detail where photons are simply missing or stretch the dynamic range when using higher ISO values. Whenever I can, I'll use ISO 1600 for
DSOs but I would like to consistently get down to 800. This would also help immensely on the "Stacker-lite" experiments I'm presently conducting.
This is why I like using optical systems
f/6 or faster, preferable
f/4 and
f/5. I can expose to single-frame background fog of about 20% in about two to three minutes at ISO 1600 depending on the quality of the sky. This Spring I hope to start using an auto-guider that will help immensely in getting longer exposures with lower ISO values even if my polar alignment is slightly off. Also, I think Canon's in-camera noise reduction (NR) circuits and long exposure imaging processing features are also greatly responsible for the single-frame images I'm presently able to capture. But however long the original exposure happens to be that's about how long it takes the Canons 77D and 80D to "process" the image. So a three minute exposure takes a total of six minutes with in-camera processing time added. That's why I've taken to using two Canon cameras, one on the primary telescope on one on the piggyback Meade 70mm or Canon telephoto. While one camera is processing an image, the other camera is exposing an image.